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Can someone explain this math problem?
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[deleted b/c poster did not cite author]
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it's the result of factoring: 2^x + 2^x = 2^x(1+1) = 2^x(2)

hope this helps.
clarify
rohit801
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look at it this way: it is clear that X + X = 2X, right- u are adding the same thing two times, so it is 2 times that thing.
in this case the expression is 2^X and that is being added twice, right? so, it becomes 2 * 2 ^x.
Now, 2 means 2^1 [2^2=4 etc]. now, we have 2^1 * 2 ^x. what do we see here- same BASE [2] being multiplied with exponents. so, we can ADD the powers [just as we can SUBTRACT the exponents when division is concerned]. so, it becomes BASE ^ [add exponenets] = 2 ^ x+1.

does that help?
Stacey Koprince
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please cite the source of this problem; if you don't, we will have to delete it (and we also won't answer it, obviously!)

please don't forget to cite sources in this folder guys!
Re: Can someone explain this math problem?
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If 2^x=A then A+A=2A

So:
2(2^x)
-------------
2^y


It can be rewritten as:

(2^1)(2^x)
---------------
2^y

With exponents with the same base, when you divide them you keep the base and subtract the exponents, and when you multiply them you add the exponents.

So we now have:

2^(x+1)
------------
2^y


And then we take the bottom part of the equation with the SAME BASE and incorporate it in the top:

1/(2^y) is the same as 2^-y


We can multiply 2^(x+1) and 2^-y

And we get 2^x-y+1
Can someone explain this math problem?
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